These commands download the ActivePython 3.5.3 image, and then run a container based on the image in interactive mode. In interactive mode you have access to Linux shell commands and you can use the command line tools included in the ActiveState language distribution. For example, enter python to work with ActivePython interactively if your are working with an ActivePython image. To exit the container, type exit.

To download a specific version of an image, you need to specify the tag to retrieve using the syntax: ActiveState/repository:tag. There is a repository for each ActiveState language distribution, and tags for each released version that is available for the language.

You can use tags to get the latest revision, or to select the precise image you need:

:latest - The latest version of the repository. For example: activestate/activepython:latest

:version - A specific version of the repository. For example: activestate/activepython:3.5.3.3505

:version-baseImage - A specific version built from a specific base image. For example: activestate/activepython:3.5.3.3505-centos

:version-baseImage-revision - A specific version that uses a specific base image and revision. For example: activestate/activepython:3.5.3.3505-centos-2

Using a Dockerfile to configure and launch your container

You can use a Dockerfile to create your own customized image based on one of the ActiveState Docker images. This allows you to configure the container with all of the settings and prerequisites required by your application. You can also use Docker Compose to link the ActiveState language containers with other containers, such as a container for the backend database or web server used by your application. This allows you to standardize your application environment in containers from development through to production.

The following example of a Dockerfile for ActivePython performs a number of actions to enable the application to run:

It creates a new image based on the ActivePython image

It sets environment variables and creates directories

It copies the needed files from the project directory on the local machine to the Docker container

ActivePython

The ActivePython distribution is installed into the /opt/activepython-<version>/ folder, with the PATH configured to run Python commands.
For version 3.x images, symbolic links are included to associate python and pip with the ActivePython distribution.

Additional packages included in the ActivePython distributions are located in /opt/ActivePython-<version>/lib/python-<version>/site-packages. You can list them by entering pip freeze at the command prompt.

ActivePerl

The ActivePerl distribution is installed into the /opt/activepython-<version>/ folder, with the PATH configured to run Perl commands.

ActiveGo

The ActiveGo distribution is installed into the /opt/activego-<version>/ folder, with the PATH configured to run Go commands.

To execute Go as soon as the container starts, you can pass go along with the required arguments in the docker run command: